Electronic component and method for forming resin layer on electronic component

ABSTRACT

An electronic component includes a plurality of laminated insulating layers, one or more surface conductors formed on a surface of the insulating layer, and an internal conductor formed at a boundary portion between the adjacent insulating layers. A thickness of the surface conductor is larger than a thickness of a thinnest layer of the insulating layers and larger than a thickness of the internal conductor.

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation of International Application No.PCT/JP2021/036635 filed on Oct. 4, 2021 which claims priority fromJapanese Patent Application No. 2020-210171 filed on Dec. 18, 2020. Thecontents of these applications are incorporated herein by reference intheir entireties.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

The present disclosure relates to an electronic component in which aninsulating layer is laminated, and a resin layer forming method for theelectronic component.

Description of the Related Art

Conventionally, as this type of electronic component, for example, anelectronic component described in Patent Document 1 (Japanese Patent No.4821302) is known. In the electronic component described in PatentDocument 1, ceramic insulating layers and conductive layers arealternately laminated. A conductor on which an inductor pattern and aland pattern are formed is provided in the uppermost conductive layer.

-   Patent Document 1: Japanese Patent No. 4821302

BRIEF SUMMARY OF THE DISCLOSURE

In such an electronic component, electrical characteristics of anelement or the like, for example, an electrical characteristic of aninductor formed by a wiring pattern provided in the electronic componentchanges according to at least a thickness and a width of a conductorforming the wiring pattern. Therefore, in the uppermost conductivelayer, it is conceivable to change the thickness and width of theconductor by trimming to adjust the electrical characteristics of anelement or the like. However, in the electronic component described inPatent Document 1, the conductor is thin because the conductor is formedby screen printing, photolithography, a thin film method, or the like.Therefore, it is difficult to trim the conductor. Even if the conductorcan be trimmed, the trimmable thickness of the conductor is small.Therefore, the electrical characteristics of an element or the likecannot be sufficiently adjusted.

Therefore, a possible benefit of the present disclosure is to solve theabove problems, and to provide an electronic component having a largetrimmable thickness of a conductor and a large adjustment range ofelectrical characteristics of an element or the like.

In order to solve the problem, an electronic component according to thepresent disclosure includes: a plurality of laminated insulating layers;one or more surface conductors formed on a surface of the insulatinglayer; and an internal conductor formed at a boundary portion betweenthe adjacent insulating layers, in which a thickness of the surfaceconductor is larger than a thickness of a thinnest layer of theinsulating layers and larger than a thickness of the internal conductor.

According to the present disclosure, it is possible to provide anelectronic component having a large trimmable thickness of a conductorand a large adjustment range of electrical characteristics of an elementor the like.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a plan view of an electronic component according to a firstembodiment of the present disclosure, excluding a plating film.

FIG. 2 is a cross-sectional view taken along line A1-A1 of theelectronic component in FIG. 1 .

FIG. 3 is a cross-sectional view taken along line B1-B1 of theelectronic component in FIG. 1 .

FIG. 4 is a plan view of an electronic component according to a secondembodiment of the present disclosure, excluding a resin layer.

FIG. 5 is a cross-sectional view taken along line A2-A2 of theelectronic component in FIG. 4 .

FIG. 6 is a cross-sectional view taken along line B2-B2 of theelectronic component in FIG. 4 .

FIG. 7 is a plan view of the electronic component according to a thirdembodiment of the present disclosure.

FIG. 8 is a cross-sectional view taken along line A3-A3 of theelectronic component in FIG. 7 .

FIG. 9 is an enlarged view of a Z1 region in FIG. 8 .

FIG. 10 is a plan view of an electronic component according to a fourthembodiment of the present disclosure.

FIG. 11 is a cross-sectional view taken along line A4-A4 of theelectronic component in FIG. 10 .

FIG. 12 is a plan view of an electronic component according to a fifthembodiment of the present disclosure.

FIG. 13 is a cross-sectional view taken along line A5-A5 of theelectronic component in FIG. 12 .

FIG. 14 is a plan view of an electronic component according to a sixthembodiment of the present disclosure.

FIG. 15 is a cross-sectional view taken along line A6-A6 of theelectronic component in FIG. 14 .

FIG. 16 is a cross-sectional view illustrating an example of a methodfor manufacturing an electronic component according to the presentdisclosure.

FIG. 17 is a cross-sectional view illustrating the example of the methodfor manufacturing an electronic component according to the presentdisclosure.

FIG. 18 is a cross-sectional view illustrating the example of the methodfor manufacturing an electronic component according to the presentdisclosure.

FIG. 19 is a cross-sectional view illustrating the example of the methodfor manufacturing an electronic component according to the presentdisclosure.

FIG. 20 is a cross-sectional view illustrating the example of the methodfor manufacturing an electronic component according to the presentdisclosure.

FIG. 21 is a cross-sectional view illustrating the example of the methodfor manufacturing an electronic component according to the presentdisclosure.

FIG. 22 is a cross-sectional view illustrating the example of the methodfor manufacturing an electronic component according to the presentdisclosure.

FIG. 23 is a cross-sectional view illustrating the example of the methodfor manufacturing an electronic component according to the presentdisclosure.

FIG. 24 is a cross-sectional view illustrating the example of the methodfor manufacturing an electronic component according to the presentdisclosure.

FIG. 25 is a view illustrating an example of a resin layer formingmethod for an electronic component according to the present disclosure.

FIG. 26 is a view illustrating the example of the resin layer formingmethod for an electronic component according to the present disclosure.

FIG. 27 is a view illustrating the example of the resin layer formingmethod for an electronic component according to the present disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

An electronic component according to one aspect of the presentdisclosure includes: a plurality of laminated insulating layers; one ormore surface conductors formed on a surface of the insulating layer; andan internal conductor formed at a boundary portion between the adjacentinsulating layers, in which a thickness of the surface conductor islarger than a thickness of a thinnest layer of the insulating layers andlarger than a thickness of the internal conductor.

According to this configuration, the surface conductor can be largelytrimmed in the thickness direction. As a result, the electricalcharacteristics of an element or the like including the surfaceconductor can be adjusted in a wide range.

In the conventional electronic component, when a first conductorrequiring trimming and a second conductor not requiring trimming aremixed on a surface of an insulating layer, the thicknesses of the firstconductor and the second conductor are almost the same. For this reason,it is difficult to trim only the first conductor by a planar processingmethod such as etching or surface grinding. On the other hand, accordingto the above configuration, it is possible to realize an electroniccomponent in which the first conductor which is a surface conductor isthicker than the second conductor. In such an electronic component,since there is a difference in thickness between the first conductor andthe second conductor, it is easy to trim only the first conductor by aplanar processing method. Therefore, the manufacturing efficiency of theelectronic component can be improved.

The thickness of the surface conductor may be larger than twice thethickness of the thinnest layer of the insulating layers.

According to this configuration, the trimmable thickness of the surfaceconductor can be increased as compared with a configuration in which thethickness of the surface conductor is smaller than twice the thicknessof the thinnest layer of the insulating layers. Therefore, it ispossible to realize an electronic component having a large adjustmentrange of electrical characteristics of an element or the like includinga surface conductor.

In addition, the thickness of the surface conductor may be larger thanthe thickness of the thickest layer of the insulating layers.

According to this configuration, the trimmable thickness of the surfaceconductor can be increased as compared with the configuration in whichthe thickness of the surface conductor is smaller than the thickness ofthe thickest layer of the insulating layers. Therefore, it is possibleto realize an electronic component having a large adjustment range ofelectrical characteristics of an element or the like including a surfaceconductor.

A plating film may be formed on at least a part of the surface of thesurface conductor.

According to this configuration, by forming the plating film on at leasta part of the surface of the surface conductor, the thickness of theconductor in which the surface conductor and the plating film areintegrated can be increased. That is, the conductor can be not onlythinned by trimming or the like, but also thickened. Therefore, it ispossible to realize an electronic component having a large adjustmentrange of electrical characteristics of an element or the like includinga surface conductor.

Further, the electronic component may include a plurality of connectionconductors formed inside the insulating layer or on the surface of theinsulating layer and electrically connected to the surface conductors,respectively.

According to this configuration, the surface conductor can form a wiringthrough which a signal is input from one connection conductor and outputto the other connection conductor. In the wiring formed of the surfaceconductor, since the surface conductor is thick, a large conductor crosssection can be obtained. This makes it possible to realize wiringcapable of applying a large current without increasing the width of thesurface conductor. In addition, the width of the surface conductor canbe reduced while maintaining the conductor cross-sectional area. Thatis, it is possible to reduce the area occupied by the surface conductoron the surface of the insulating layer while maintaining the allowablecurrent value of the wiring. Therefore, the electronic component can bedownsized, and wiring, components, and the like can be further arranged.

At least one of the plurality of connection conductors may be a viaconductor penetrating one of the plurality of insulating layers in alamination direction of the insulating layers.

According to this configuration, the via conductor of the plurality ofconnection conductors is not exposed to the surface of the insulatinglayer. Therefore, it is possible to reduce members for suppressing theinfluence of atmosphere, moisture, and the like on the surfaceconductor. Therefore, since the number of members of the electroniccomponent is reduced, the manufacturing efficiency of the electroniccomponent can be improved.

In addition, the electronic component may include an inductor conductorelectrically connected to the surface conductor via the connectionconductor, and the surface conductor may constitute at least a part ofthe inductor together with the connection conductor and the inductorconductor.

According to this configuration, since the surface conductor is thick inat least a part of the inductor, a larger conductor cross section can beobtained. This reduces the insertion loss of the inductor. In addition,since the trimmable thickness of the surface conductor is large, theadjustment range of the electrical characteristics of the inductor islarge.

In addition, the surface conductor may include a first portion that isthicker than the thickness of the thinnest layer of the insulatinglayers and is thicker than the thickness of the internal conductor, anda second portion that is continuous with the first portion along thesurface of the insulating layer and is thinner than the first portion.

According to this configuration, there is a difference in thickness at aboundary portion between the first portion and the second portion, and ashadow is generated at the boundary portion. This shadow can be used asa directional mark indicating the direction of the electronic component.This eliminates the need to separately provide a directional mark, sothat the manufacturing efficiency of the electronic component can beimproved. In addition, since the area occupied by the directional markis unnecessary on the surface of the insulating layer, it is possible toreduce the size of the electronic component and to further arrangewiring, components, and the like.

Further, the electronic component may have a rotationally symmetricouter shape in plan view, and a boundary portion between the firstportion and the second portion in the surface conductor may be arrangedin a non-rotationally symmetric manner with respect to a center point ofthe rotational symmetry of the electronic component.

According to this configuration, at least one shadow generated by theboundary portion between the first portion and the second portion in thesurface conductor appears at a non-rotationally symmetric position withrespect to the center point when the electronic component is viewed inplan view. Therefore, the shadow that can be used as a directional markindicating the direction of the electronic component can be realized.

Further, the electronic component may have a rotationally symmetricouter shape in plan view, and the surface conductor may be arranged in anon-rotationally symmetric manner with respect to a center point of therotational symmetry of the electronic component in plan view.

According to this configuration, the surface conductor can indicate thedirection of the electronic component by its position and shape in planview. That is, the surface conductor can also serve as a directionalmark indicating the direction of the electronic component. Thiseliminates the need to separately provide a directional mark, so thatthe manufacturing efficiency of the electronic component can beimproved. In addition, since the area occupied by the directional markis unnecessary on the surface of the insulating layer, it is possible toreduce the size of the electronic component and to further arrangewiring, components, and the like.

The electronic component may include a resin layer or a glass layercovering at least a part of the surface conductor.

According to this configuration, at least a part of the surfaceconductor can be protected by the resin layer or the glass layer fromthe influence of foreign matter, impact, or the like from the outside.In addition, the resin layer or the glass layer improves the mechanicalstrength of the electronic component. Furthermore, it is possible toarrange a shield that shields electromagnetic waves at a position facingthe electronic component via the resin layer or the glass layer.

At least a part of the resin layer or at least a part of the glass layermay be thicker than a thickness of a thinnest layer of the insulatinglayers and thicker than a thickness of the internal conductor.

According to this configuration, it is possible to realize a resin layeror a glass layer capable of more reliably protecting the surfaceconductor from the influence of foreign matter, impact, or the like fromthe outside and further improving the mechanical strength of theelectronic component.

The electronic component may further include a via conductor penetratingone of the plurality of insulating layers in the lamination direction ofthe insulating layers, and the thickness of the surface conductor may belarger than a length of the via conductor in the lamination direction.

According to this configuration, the surface conductor can be largelytrimmed in the thickness direction. As a result, the electricalcharacteristics of an element or the like including the surfaceconductor can be adjusted in a wide range.

In the conventional electronic component, when a first conductorrequiring trimming and a second conductor not requiring trimming aremixed on a surface of an insulating layer, the thicknesses of the firstconductor and the second conductor are almost the same. For this reason,it is difficult to trim only the first conductor by a planar processingmethod such as etching or surface grinding. On the other hand, accordingto the above configuration, it is possible to realize an electroniccomponent in which the first conductor which is a surface conductor isthicker than the second conductor. In such an electronic component,since there is a difference in thickness between the first conductor andthe second conductor, it is easy to trim only the first conductor by aplanar processing method. Therefore, the manufacturing efficiency of theelectronic component can be improved.

In addition, the surface conductor may include a first portion that isthicker than the length of the via conductor in the laminationdirection, and a second portion that is continuous with the firstportion along a surface of the insulating layer and is thinner than thefirst portion.

According to this configuration, there is a difference in thickness at aboundary portion between the first portion and the second portion, and ashadow is generated at the boundary portion. This shadow can be used asa directional mark indicating the direction of the electronic component.This eliminates the need to separately provide a directional mark, sothat the manufacturing efficiency of the electronic component can beimproved. In addition, since the area occupied by the directional markis unnecessary on the surface of the insulating layer, it is possible toreduce the size of the electronic component and to further arrangewiring, components, and the like.

The surface conductor may constitute at least a part of the inductor.

According to this configuration, since the surface conductor is thick inat least a part of the inductor, a larger conductor cross section can beobtained. This reduces the insertion loss of the inductor. In addition,since the trimmable thickness of the surface conductor is large, theadjustment range of the electrical characteristics of the inductor islarge.

A resin layer forming method for an electronic component according to anaspect of the present disclosure includes: an immersion step ofimmersing an electronic component not including a resin layer in a resinto attach the resin to an outer surface of the electronic componentincluding a surface of the insulating layer; a curing step of curing theresin attached to at least a part of the surface conductor to form aresin layer; and a removal step of removing the uncured resin from theelectronic component.

According to this method, the resin layer can be formed by attaching theresin to the entire electronic component and curing the resin only at adesired portion on the electronic component. Therefore, unlike themethod for forming the resin layer by applying the resin only to adesired portion, it is not necessary to align the electronic componentsin order to attach the resin. Therefore, the manufacturing efficiency ofthe electronic component can be improved.

Hereinafter, embodiments of the present disclosure will be describedwith reference to the drawings. Note that the present disclosure is notlimited to the following embodiments.

In the drawings, substantially the same elements are denoted by the samereference numerals, and description thereof is omitted.

Hereinafter, for convenience of description, terms indicating directionssuch as “upper surface”, “lower surface”, “upper side”, “right side”,and “left side” are used, but these terms are not intended to limit ausage state or the like of the electronic component according to thepresent disclosure.

First Embodiment

An electronic component according to a first embodiment of the presentdisclosure will be described with reference to FIGS. 1 to 3 . FIG. 1 isa plan view of an electronic component according to a first embodimentof the present disclosure, excluding a plating film. FIG. 2 is across-sectional view taken along line A1-A1 of the electronic componentin FIG. 1 . FIG. 3 is a cross-sectional view taken along line B1-B1 ofthe electronic component in FIG. 1 .

As illustrated in FIGS. 2 and 3 , in the first embodiment, an electroniccomponent 1A includes five laminated insulating layers 2. The fiveinsulating layers 2 include a first surface layer 21 constituting theupper surface of the electronic component 1A, a second surface layer 22constituting the lower surface, and an intermediate layer 23 laminatedbetween the first surface layer 21 and the second surface layer 22. Inaddition, the electronic component 1A includes via conductors 3 thatpenetrate one insulating layer 2. As illustrated in FIG. 1 , a surfaceconductor 4 and a land conductor 5 are formed on a surface 21 a of thefirst surface layer 21.

The insulating layer 2 illustrated in FIGS. 2 and 3 is formed, forexample, by firing a sheet having a sinterable ceramic powder. Thethickness of the insulating layer 2 is, for example, 1 to 150 μm. In thefirst embodiment and a second embodiment described later, thethicknesses of the five insulating layers 2 are the same.

The via conductor 3 is formed by firing a conductive paste having aconductive powder. The length of the via conductor 3 in the penetratingdirection is the same as or substantially the same as the thickness ofone insulating layer 2. The via conductor 3 has, for example, atruncated cone shape having a diameter of 20 to 200 μm.

As illustrated in FIGS. 1 to 3 , the surface conductor 4 is formed onthe surface 21 a of the first surface layer 21. The surface conductor 4is formed by firing a conductive paste having a conductive powder.

As illustrated in FIG. 2 , two via conductors 3 formed in the firstsurface layer 21 are connected to both end portions of the surfaceconductor 4. These two via conductors 3 are an example of a “connectionconductor” in the present disclosure. The via conductors 3 penetrate oneof the laminated insulating layers 2 in the lamination direction of theinsulating layers 2 (hereinafter, simply referred to as “laminationdirection”). The electric signal applied to one via conductor 3 istransmitted to one end portion of the surface conductor 4, transmittedto the other end portion of the surface conductor 4, and output to theother via conductor 3. In this manner, the surface conductor 4 canfunction as wiring.

As illustrated in FIGS. 2 and 3 , the thickness of the surface conductor4 is larger than the length of the via conductor 3 in the penetratingdirection. The thickness of the surface conductor 4 is, for example, 2to 10 times the thickness of the insulating layer 2. The surfaceconductor 4 has, for example, a width of 20 to 200 μm and a length of 50to 3000 μm. In the present embodiment, the surface conductor 4 has anelongated shape in which both end portions are rounded in plan viewillustrated in FIG. 1 .

As illustrated in FIG. 1 , the surface conductor 4 includes surfaceconductors 4A having a constant or substantially constant thickness overthe entire surface conductor 4A, and a surface conductor 4B having apartially different thickness.

As illustrated in FIG. 2 , the surface conductor 4B includes a firstportion 41 thicker than the length of the via conductor 3 in thepenetrating direction, and a second portion 42 continuous with the firstportion 41 along the surface 21 a of the first surface layer 21 andthinner than the first portion 41. In such a surface conductor 4B, asillustrated in FIG. 1 , shadows S1 are generated by a difference inthickness between the first portion 41 and the second portion 42. Forexample, the shadows S1 illustrated in FIG. 1 indicate shadows generatedwhen the electronic component 1A is illuminated from slightly above bothend portions of the surface conductor 4.

The surface conductor 4A and the first portion 41 of the surfaceconductor 4B can be trimmed in the thickness direction by a planarprocessing method after formation. Examples of the planar processingmethod include etching and surface grinding.

As illustrated in FIGS. 1 and 3 , the land conductor 5 for connecting toanother electronic component or the like is provided on the surface 21 aof the first surface layer 21. In the present embodiment, the landconductor 5 is formed to be thinner than the second portion 42 of thesurface conductor 4B.

As illustrated in FIGS. 2 and 3 , a plating film 6 is formed on thesurfaces of the surface conductor 4 and the land conductor 5. Theplating film 6 suppresses the influence of atmosphere, moisture, and thelike on the surface conductor 4 and the land conductor 5. The platingfilm 6 is, for example, a Ni—Sn plating film, a Ni-electroless Auplating film, or the like.

Note that the plating film 6 is formed as necessary, and may be formedonly on a part of the surface conductor 4 or the land conductor 5, ormay not be formed, for example.

As illustrated in FIGS. 2 and 3 , an internal conductor 7 extending in adirection in which the insulating layer 2 extends is formed at aboundary portion between the plurality of insulating layers 2. Thethickness of the internal conductor 7 is, for example, 2 to 10 μm.

As illustrated in FIG. 1 , the electronic component 1A has arotationally symmetric outer shape with respect to a virtual centerpoint P of the electronic component 1A in plan view. Here, “rotationallysymmetric” means that the relative position and the shape with respectto the virtual center point P coincide with those before rotation whenthe electronic component 1A is rotated around the virtual center point Pin plan view. In the present embodiment, the outer shape of theelectronic component 1A is rectangular. In this case, when theelectronic component 1A is rotated by 180 degrees around the virtualcenter point P in plan view, the relative position and the shape of theelectronic component 1A with respect to the virtual center point Pcoincide with those before the rotation. Therefore, the outer shape ofthe electronic component 1A in the present embodiment is rotationallysymmetric.

The surface conductor 4 and the land conductor 5 are arrangedrotationally symmetrically with respect to the virtual center point P onthe surface 21 a of the first surface layer 21. Therefore, the directionof the electronic component 1A cannot be determined from the outer shapeof the electronic component 1A in plan view and the shapes and positionsof the surface conductor 4 and the land conductor 5.

However, in the present embodiment, the direction of the electroniccomponent 1A can be determined in plan view by the shadows S1 caused bythe difference in thickness in the surface conductor 4B. In the presentembodiment, the surface conductor 4B is arranged on the left side of thevirtual center point P in the plan view illustrated in FIG. 1 . On theother hand, the surface conductor 4B is not arranged on the right sideof the virtual center point P in the plan view illustrated in FIG. 1 .Therefore, when the electronic component 1A is viewed in plan view, theshadows S1 are seen only on the left side of the virtual center point P.Therefore, the direction of the electronic component 1A can bedetermined from the position of the shadow S1 in plan view. That is, theshadow S1 can be used as a directional mark indicating the direction ofthe electronic component 1A depending on the position in the plan view.In addition, since the visibility of the shadow S1 is improved byilluminating the electronic component 1A, it is easier to determine thedirection of the electronic component 1A.

The shadow S1 occurs at a boundary portion 43 between the first portion41 and the second portion 42 of the surface conductor 4B. As describedabove, in the present embodiment, the surface conductor 4B having theboundary portion 43 is arranged only on the left side of the virtualcenter point P in the plan view illustrated in FIG. 1 . Therefore, whenthe boundary portion 43 is rotated around the virtual center point P inplan view, the relative position and the shape of the boundary portion43 with respect to the virtual center point P do not coincide with thosebefore and after the rotation. That is, the boundary portion 43 isarranged in a non-rotationally symmetric manner with respect to thevirtual center point P. Therefore, the shadow S1 can be used as adirectional mark.

Note that the mode in which the boundary portion 43 is arranged in anon-rotationally symmetric manner with respect to the virtual centerpoint P is not limited to the above-described mode. As long as theboundary portion 43 is arranged in a non-rotationally symmetric mannerwith respect to the virtual center point P, the shadow S1 can be used asa directional mark regardless of the number of surface conductors 4B andthe number of boundary portions 43 formed on each surface conductor 4B.For example, even when the electronic component 1A has two boundaryportions 43 arranged on both left and right sides of the virtual centerpoint P in the plan view illustrated in FIG. 1 , at least one of theshapes of the two boundary portions 43 and the relative positions withrespect to the virtual center point P only needs to be different fromeach other. In this case, when one boundary portion 43 is rotated aroundthe virtual center point P, the one boundary portion 43 does not overlapthe other boundary portion 43 so as to coincide with the other boundaryportion 43. That is, the two boundary portions 43 are arranged in anon-rotationally symmetric manner with respect to the virtual centerpoint P.

According to the electronic component 1A according to the presentembodiment, the thickness of the surface conductor 4 is larger than thelength of the via conductor 3 in the lamination direction. Therefore,the surface conductor 4 can be largely trimmed in the thicknessdirection. As a result, the electrical characteristics of an element orthe like including the surface conductor 4 can be adjusted in a widerange.

In the conventional electronic component, when a first conductorrequiring trimming and a second conductor not requiring trimming aremixed on a surface of an insulating layer, the thicknesses of the firstconductor and the second conductor are almost the same. For this reason,it is difficult to trim only the first conductor by a planar processingmethod such as etching or surface grinding. On the other hand, accordingto the electronic component 1A according to the present embodiment, itis possible to realize the electronic component 1A in which the surfaceconductor 4 is thicker than the land conductor 5. In such an electroniccomponent 1A, since there is a difference in thickness between thesurface conductor 4 and the land conductor 5, it is easy to trim onlythe surface conductor 4 by a planar processing method. Therefore, themanufacturing efficiency of the electronic component 1A can be improved.

In addition, the electronic component 1A according to the presentembodiment includes a plurality of via conductors 3 each electricallyconnected to the surface conductor 4. As a result, the surface conductor4 can form a wiring through which a signal is input from one viaconductor 3 and a signal is output to the other via conductor 3. In thewiring formed of the surface conductor 4, since the surface conductor 4is thick, a large conductor cross section can be obtained. This makes itpossible to realize wiring capable of applying a large current withoutincreasing the width of the surface conductor 4. In addition, the widthof the surface conductor 4 can be reduced while maintaining theconductor cross-sectional area. That is, it is possible to reduce thearea occupied by the surface conductor 4 on the surface 21 a of theinsulating layer 2 while maintaining the allowable current value of thewiring. Therefore, the electronic component 1A can be downsized, andwiring, components, and the like can be further arranged.

In addition, according to the electronic component 1A according to thepresent embodiment, the via conductor 3 among the plurality ofconnection conductors is not exposed on the surface 21 a of theinsulating layer 2. Therefore, it is possible to reduce members forsuppressing the influence of atmosphere, moisture, and the like on thesurface conductor 4. Therefore, since the number of members of theelectronic component 1A is reduced, the manufacturing efficiency of theelectronic component 1A can be improved.

In addition, according to the electronic component 1A according to thepresent embodiment, the surface conductor 4 includes the first portion41 thicker than the length of the via conductor 3 in the laminationdirection, and the second portion 42 continuous with the first portion41 along the surface 21 a of the insulating layer 2 and thinner than thefirst portion 41. At this time, there is a difference in thickness atthe boundary portion 43 between the first portion 41 and the secondportion 42, and the shadow S1 is generated at the boundary portion 43.The shadow S1 can be used as a directional mark indicating the directionof the electronic component 1A. This eliminates the need to separatelyprovide a directional mark, so that the manufacturing efficiency of theelectronic component 1A can be improved. In addition, since the areaoccupied by the directional mark is unnecessary on the surface 21 a ofthe insulating layer 2, it is possible to reduce the size of theelectronic component 1A and to further arrange wiring, components, andthe like.

In addition, according to the electronic component 1A according to thepresent embodiment, the boundary portion 43 between the first portion 41and the second portion 42 in the surface conductor 4 is arranged in anon-rotationally symmetric manner with respect to the center point P ofthe rotational symmetry of the electronic component 1A. As a result, atleast one shadow S1 generated by the boundary portion 43 appears at anon-rotationally symmetric position with respect to the center point Pwhen the electronic component 1A is viewed in plan view. Therefore, theshadow S1 that can be used as a directional mark indicating thedirection of the electronic component 1A can be realized.

Second Embodiment

Next, an electronic component according to a second embodiment of thepresent disclosure will be described with reference to FIGS. 4 to 6 .FIG. 4 is a plan view of an electronic component according to the secondembodiment of the present disclosure, excluding a resin layer. FIG. 5 isa cross-sectional view taken along line A2-A2 of the electroniccomponent in FIG. 4 . FIG. 6 is a cross-sectional view taken along lineB2-B2 of the electronic component in FIG. 4 .

An electronic component 1B according to the second embodiment isdifferent from the electronic component 1A according to the firstembodiment in that a surface conductor 4 constitutes a part of aninductor 9. As illustrated in FIG. 4 , the surface conductor 4 isarranged in a non-rotationally symmetric manner with respect to avirtual center point P. As illustrated in FIGS. 5 and 6 , the surfaceconductor 4 is covered with a resin layer 8. The land conductor 5 isformed on the surface 22 a of the second surface layer 22.

In the second embodiment, as illustrated in FIG. 4 , three surfaceconductors 4 are arranged in parallel to each other on a surface 21 a ofa first surface layer 21.

As illustrated in FIG. 4 , the three surface conductors 4 areelectrically connected via via conductors 3 connected to the endportions of the surface conductors 4 and two internal conductors 7. Thetwo internal conductors 7 connect the via conductors 3 arranged on theopposite sides of the adjacent surface conductors 4. The via conductor 3connected to the end portion of each surface conductor 4 is an exampleof a “connection conductor” in the present disclosure. The two internalconductors 7 are an example of an “inductor conductor” in the presentdisclosure.

As a result, the via conductors 3, the surface conductors 4, and theinternal conductors 7 constitute the coil-shaped inductor 9. In thepresent embodiment, the winding axis direction of the inductor 9 is adirection perpendicular to the direction in which the insulating layer 2spreads and the direction in which the surface conductor 4 extends(left-right direction in FIG. 4 , and depth direction of the papersurface in FIG. 5 ).

As illustrated in FIG. 4 , the electronic component 1B has arotationally symmetric outer shape in plan view, similarly to theelectronic component 1A. That is, when the electronic component 1B isrotated around the virtual center point P in plan view, the relativeposition and the shape with respect to the virtual center point Pcoincide with those before the rotation. On the other hand, in thepresent embodiment, the three surface conductors 4 are arranged only onthe right side of the virtual center point P and are not arranged on theleft side in the plan view illustrated in FIG. 4 . Therefore, when thethree surface conductors 4 are rotated around the virtual center point Pin plan view, the relative positions and the shapes of the three surfaceconductors 4 with respect to the virtual center point P do not coincidewith those before and after the rotation. That is, the surfaceconductors 4 are arranged in a non-rotationally symmetric manner withrespect to the virtual center point P. Therefore, the direction of theelectronic component 1B can be determined from the positions of thesurface conductors 4 in plan view. Therefore, the surface conductors 4can be used as directional marks indicating the direction of theelectronic component 1B by their positions and shapes in plan view.

For example, as in the present embodiment, the surface conductors 4 canbe used as directional marks when being arranged in a non-rotationallysymmetric manner with respect to the virtual center point P in planview. As long as such an arrangement is satisfied, one or a plurality ofsurface conductors 4 can indicate the direction of the electroniccomponent 1B in plan view. For example, even when the surface conductors4 are arranged on both the left and right sides of the virtual centerpoint P in the plan view illustrated in FIG. 1 , at least one of theshapes of the surface conductor 4 arranged on the right side and thesurface conductor 4 arranged on the left side and the relative positionswith respect to the virtual center point P only needs to be different.In this case, when the surface conductor 4 arranged on the right side isrotated around the virtual center point P, the surface conductor 4arranged on the right side does not overlap the surface conductor 4arranged on the left side so as to coincide with the surface conductor 4arranged on the left side. That is, the surface conductors 4 arranged onthe left and right sides are arranged in a non-rotationally symmetricmanner with respect to the virtual center point P.

Further, since the surface conductor 4 is thick, when the electroniccomponent 1B is illuminated, a clear shadow S2 is generated by thesurface conductor 4. The shadow S2 occurs, for example, in a case wherelight can be transmitted through the resin layer 8 described later, in acase where the surface conductor 4 protrudes from the surface of theresin layer 8, in a case where the electronic component 1B does notinclude the resin layer 8, or the like. The shadow S2 illustrated inFIG. 4 indicates a shadow when the electronic component 1B including theresin layer 8 through which light can be transmitted is illuminated fromdiagonally upper right of the electronic component 1B. Note that such ashadow S2 occurs in each of the surface conductors 4, but FIG. 4representatively illustrates only the shadow S2 of the surface conductor4 closest to the virtual center point P. According to such a shadow S2,since the visibility of the surface conductor 4 in plan view is good, itis easy to determine the direction of the electronic component 1B.

As illustrated in FIGS. 5 and 6 , the resin layer 8 that covers thesurface conductor 4 is formed on the surface 21 a of the first surfacelayer 21. For the resin layer 8, for example, an acrylic resin, aurethane resin, an epoxy resin, a phenol resin, a silicone resin,polyimide, or the like is used. In the present embodiment, the resinlayer 8 is formed over the entire surface 21 a of the first surfacelayer 21. In the present embodiment, the thickness of the resin layer 8is larger than any of the length of the via conductor 3 in thepenetrating direction, the thickness of each insulating layer 2, and thethickness of each internal conductor 7 in a portion not overlapping thesurface conductor 4 in plan view. In the present embodiment, since thefive insulating layers 2 have the same thickness, it can be said thatthe thickness of the portion of the resin layer 8 is larger than thethickness of the thinnest layer of the five insulating layers 2. Here,the thickness of the resin layer 8 refers to, for example, the thicknessfrom the surface 21 a of the first surface layer 21 to an outer surface8 a of the resin layer 8 in the lamination direction.

The resin layer 8 formed on the side of the surface conductor 4 preventsthe surface conductor 4 from being peeled off from the surface 21 a ofthe first surface layer 21 or from being displaced on the surface 21 a.In addition, since the resin layer 8 is covered with the surfaceconductor 4, the influence of atmosphere, moisture, and the like on thesurface conductor 4 is suppressed. Further, by forming the resin layer8, the mechanical strength of the electronic component 1B can beimproved. Furthermore, a shield (not illustrated) that shieldselectromagnetic waves can be provided on the outer surface 8 a of theresin layer 8. By interposing the resin layer 8 between the shield andthe surface conductor 4, it is possible to realize a shield that is notelectrically connected to the surface conductor 4.

According to the electronic component 1B according to the presentembodiment, the surface conductor 4 constitutes at least a part of theinductor 9 together with the via conductors 3 and the internal conductor7. In at least a part of such an inductor 9, since the surface conductor4 is thick, a larger conductor cross section can be obtained. Thisreduces the insertion loss of the inductor 9. In addition, since thetrimmable thickness of the surface conductor 4 is large, the adjustmentrange of the electrical characteristics of the inductor 9 is large.

In addition, according to the electronic component 1B according to thepresent embodiment, the surface conductor 4 is arranged in anon-rotationally symmetric manner with respect to the center point P ofthe rotational symmetry of the electronic component 1B. Therefore, thedirection of the electronic component 1B can be indicated by theposition and shape of the surface conductor 4 in plan view. That is, thesurface conductor 4 can also serve as a directional mark indicating thedirection of the electronic component 1B. This eliminates the need toseparately provide a directional mark, so that the manufacturingefficiency of the electronic component 1B can be improved. In addition,since the area occupied by the directional mark is unnecessary on thesurface 21 a of the insulating layer 2, it is possible to reduce thesize of the electronic component 1B and to further arrange wiring,components, and the like.

In addition, according to the electronic component 1B according to thepresent embodiment, the electronic component 1B includes the resin layer8 that covers at least a part of the surface conductor 4. The resinlayer 8 can protect the surface conductor 4 from the influence offoreign matter, impact, or the like from the outside. In addition, theresin layer 8 improves the mechanical strength of the electroniccomponent 1B. Furthermore, a shield that shields electromagnetic wavescan be arranged at a position facing the electronic component 1B via theresin layer 8.

In addition, according to the electronic component 1B according to thepresent embodiment, a part of the resin layer 8 is thicker than thethickness of the thinnest layer of the insulating layers 2 and thickerthan the thickness of the internal conductor 7. As a result, it ispossible to realize the resin layer 8 capable of more reliablyprotecting the surface conductor 4 from the influence of foreign matter,impact, or the like from the outside and further improving themechanical strength of the electronic component 1B.

Third Embodiment

Next, an electronic component according to a third embodiment of thepresent disclosure will be described with reference to FIGS. 7 to 9 .FIG. 7 is a plan view of the electronic component according to the thirdembodiment of the present disclosure. FIG. 8 is a cross-sectional viewtaken along line A3-A3 of the electronic component in FIG. 7 . FIG. 9 isan enlarged view of a Z1 region in FIG. 8 .

As illustrated in FIG. 7 , the electronic component 1C according to thethird embodiment has a substantially rectangular outer shape when viewedfrom the lamination direction.

As illustrated in FIG. 8 , the electronic component 1C includes elevenlaminated insulating layers 2. The eleven insulating layers 2 include afirst surface layer 21 constituting the upper surface of the electroniccomponent 1C, a second surface layer 22 constituting the lower surface,and nine intermediate layers 23A to 23I laminated between the firstsurface layer 21 and the second surface layer 22.

The thicknesses of the insulating layers 2 in the lamination directionmay be the same as or different from each other. In the exampleillustrated in FIG. 8 , the intermediate layer 23A is the thinnest amongthe eleven insulating layers 2. The thickness T2 of the intermediatelayer 23A is, for example, 5 μm. The intermediate layer 23D is thethickest among the eleven insulating layers 2. The thickness T3 of theintermediate layer 23D is, for example, 40 μm.

As indicated by an alternate long and short dash line in FIG. 7 , oneland conductor 5A functioning as a ground electrode and two landconductors 5B functioning as an input electrode or an output electrodeare provided on a surface 22 a (see FIG. 8 ) of the second surface layer22. In the example illustrated in FIG. 7 , the land conductor 5A isarranged at the center in the long-side direction (the left-rightdirection in FIG. 7 ) of the outer shape of the electronic component 1Cwhen viewed from the lamination direction. The two land conductors 5Bare arranged so as to sandwich the land conductor 5A in the long-sidedirection.

Four surface conductors 4 are arranged on the surface 21 a of the firstsurface layer 21. The four surface conductors 4 include surfaceconductors 4C to 4E. Each of the surface conductors 4 extends in theshort-side direction (up-down direction in FIG. 7 ) of the outer shapeof the electronic component 1C when viewed from the laminationdirection. As illustrated in FIG. 8 , a plating film 6 is formed on thesurface of the surface conductor 4.

In the example illustrated in FIG. 8 , similarly to the surfaceconductor 4A in the first embodiment, the surface conductor 4 has aconstant or substantially constant thickness over the entire surfaceconductor 4. The thickness T1 of the surface conductor 4 is larger thanthe thickness T2 of the intermediate layer 23A and larger than thethickness of an internal conductor 7 (described later). For example, thethickness T1 of the surface conductor 4 is larger than the thickness ofthe thickest internal conductor 7 included in the electronic component1C. In the present embodiment, the thickness of the surface conductor 4is larger than twice the thickness T2 of the intermediate layer 23A andlarger than the thickness T3 of the intermediate layer 23D. In addition,the thickness of the surface conductor 4 may be larger than twice thethickness T3 of the intermediate layer 23D. Here, the “thickness of thesurface conductor 4” does not include the thickness of the plating film6 formed on the surface of the surface conductor 4. The thickness of thesurface conductor 4 is, for example, 50 μm.

In the example illustrated in FIG. 7 , the plating film 6 is formed onthe entire surface of each surface conductor 4. The plating film 6 maybe formed only on a part of the surface of the surface conductor 4. Thethickness of the plating film 6 is, for example, 5 to 20 μm.

The surface conductor 4 and the plating film 6 constitute an integratedconductor. Therefore, the current flowing through the surface conductor4 also flows through the plating film 6.

As indicated by a broken line in FIG. 7 , the electronic component 1Cincludes five internal conductors 7. The five internal conductors 7include internal conductors 7A to 7E. The internal conductors 7 areformed at boundary portions between the adjacent insulating layers 2.Each of the internal conductors 7A and 7D is electrically connected toeach of the land conductors 5B. As illustrated in FIG. 8 , the internalconductor 7E is connected to the land conductor 5A via the plurality ofvia conductors 3. Since the land conductor 5A is grounded, the internalconductor 7E is grounded. Note that the internal conductor 7E only needsto be electrically connected to the land conductor 5A, and may beconnected to the land conductor 5A via a component other than the viaconductors 3.

As illustrated in FIG. 7 , the four internal conductors 7A to 7D arearranged so as not to face each other in the lamination direction. Thatis, the four internal conductors 7A to 7D do not overlap when viewedfrom the lamination direction. On the other hand, the internal conductor7E is arranged so as to face the internal conductors 7A to 7D with theinsulating layer 2 interposed therebetween in the lamination direction(see, for example, FIG. 8 .). As a result, capacitors 17A to 17D areformed by the internal conductors 7A to 7D and the internal conductor7E, respectively. The internal conductor 7A and the internal conductor7D face an internal conductor (not illustrated) via the insulating layer2 to form capacitive coupling.

As illustrated in FIG. 8 , the internal conductor 7C is connected to thesurface conductor 4E via eight via conductors 3 penetrating the firstsurface layer 21 and the seven intermediate layers 23A to 23G. Theinternal conductor 7E is connected to the surface conductor 4E via ninevia conductors 3 penetrating the first surface layer 21 and the eightintermediate layers 23A to 23H. Note that the internal conductor 7C andthe surface conductor 4E and the internal conductor 7E and the surfaceconductor 4E may be connected via one or a plurality of via conductors3.

In the example illustrated in FIG. 8 , the plurality of via conductors 3connecting the internal conductors 7C and 7E and the surface conductor4E are continuously arranged in the lamination direction as so-calledcontinuous vias. In the example illustrated in FIG. 9 , each viaconductor 3 in the continuous vias has a tapered shape when viewed froma direction orthogonal to the lamination direction. In this case, eachvia conductor 3 has a truncated cone shape. Each via conductor 3 is notlimited to the truncated cone shape, and may have, for example, acylindrical shape.

Similarly to the surface conductor 4E, each of the surface conductors4C, 4D, and 4F is connected to each of the internal conductors 7A, 7B,and 7D via the via conductor 3. Each of the surface conductors 4C, 4D,and 4F is connected to the internal conductor 7E via the via conductor3. Note that the surface conductors 4C to 4F and the internal conductors7A to 7D or the internal conductor 7E only need to be electricallyconnected, and may be connected via a component other than the viaconductor 3.

The surface conductor 4E and the via conductor 3 connecting the surfaceconductor 4E and each of the internal conductors 7C and 7E constitute aninductor 9C. Similarly, the surface conductors 4C, 4D, and 4F and thevia conductor 3 connecting the surface conductors 4C, 4D, and 4F and theinternal conductors 7A, 7B, 7D, and 7E constitute inductors 9A, 9B, and9D, respectively. That is, each of the surface conductors 4C to 4Fconstitutes a part of each of the inductors 9A to 9D. The via conductor3 connected to each of the surface conductors 4C to 4F is an example ofa “connection conductor” in the present disclosure.

Each of the inductors 9A to 9D and each of the capacitors 17A to 17Dform an LC parallel resonator in which one inductor and one capacitorare connected in parallel. That is, the electronic component 1C includesfour LC parallel resonators. The four LC parallel resonators arearranged along the long-side direction of the outer shape of theelectronic component 1C when viewed from the lamination direction.Therefore, when the adjacent LC parallel resonators areelectromagnetically coupled, the electronic component 1C functions as aband pass filter.

According to the electronic component 1C according to the presentembodiment, the thickness of the surface conductor 4 is larger than thethickness of the thinnest intermediate layer 23A of the insulatinglayers 2 and larger than the thickness of the internal conductor 7.Therefore, the surface conductor 4 can be largely trimmed in thethickness direction. As a result, the electrical characteristics of theinductors 9A to 9D including the surface conductor 4 can be adjusted ina wide range.

In the electronic component 1C according to the present embodiment, thethickness of the surface conductor 4 is larger than twice the thicknessof the thinnest intermediate layer 23A of the insulating layers 2.Therefore, the trimmable thickness of the surface conductor 4 can beincreased as compared with a configuration in which the thickness of thesurface conductor 4 is smaller than twice the thickness of the thinnestintermediate layer 23A of the insulating layers 2. Therefore, it ispossible to realize the electronic component 1C having a largeadjustment range of the electrical characteristics of the inductors 9Ato 9D including the surface conductor 4.

In the electronic component 1C according to the present embodiment, thethickness of the surface conductor 4 is larger than the thickness of thethickest intermediate layer 23D of the insulating layers 2. Therefore,the trimmable thickness of the surface conductor 4 can be increased ascompared with the configuration in which the thickness of the surfaceconductor 4 is smaller than the thickness of the thickest intermediatelayer 23D of the insulating layers 2. Therefore, it is possible torealize the electronic component 1C having a large adjustment range ofthe electrical characteristics of the inductors 9A to 9D including thesurface conductor 4.

In addition, according to the electronic component 1C according to thepresent embodiment, by forming the plating film 6 on at least a part ofthe surface of the surface conductor 4, the thickness of the conductorin which the surface conductor 4 and the plating film 6 are integratedcan be increased. That is, the conductor can be not only thinned bytrimming or the like, but also thickened. Therefore, it is possible torealize the electronic component 1C having a large adjustment range ofthe electrical characteristics of the inductors 9A to 9D including thesurface conductor 4.

In the present embodiment, when the surface conductor 4 is trimmed andthinned, the conductor cross-sectional area of the surface conductor 4decreases. At this time, the inductance values of the inductors 9A to 9Dincrease. As a result, the resonance frequency of the LC parallelresonator including the inductors 9A to 9D and the capacitors 17A to 17Ddecreases. On the other hand, when the plating film 6 is formed on thesurface of the surface conductor 4, the conductor in which the surfaceconductor 4 and the plating film 6 are integrated becomes thick, so thatthe cross-sectional area of the conductor increases. Therefore, theinductance values of the inductors 9A to 9D are low contrary to the casewhere the surface conductor 4 becomes thin. As a result, the resonancefrequency increases. In addition, the thickness of the conductor can befinely adjusted, for example, by changing the plating processing time.Therefore, the electrical characteristics of the inductor 9 includingthe surface conductor 4 can be adjusted with high accuracy.

Fourth Embodiment

Next, an electronic component according to a fourth embodiment of thepresent disclosure will be described with reference to FIGS. 10 and 11 .FIG. 10 is a plan view of the electronic component according to thefourth embodiment of the present disclosure. FIG. 11 is across-sectional view taken along line A4-A4 of the electronic componentin FIG. 10 .

The electronic component 1D according to the fourth embodiment isdifferent from the electronic component 1C according to the thirdembodiment in that a surface conductor 4G is further provided. Inaddition, the electronic component 1D does not include the surfaceconductors 4D and 4E and the internal conductors 7B and 7C. The platingfilm 6 is not formed on the surface of the surface conductor 4.

As illustrated in FIG. 10 , the electronic component 1D includes threesurface conductors 4 and three internal conductors 7. The three surfaceconductors include surface conductors 4C, 4F, and 4G. The three internalconductors 7 include internal conductors 7A, 7D, and 7E.

As illustrated in FIG. 11 , the internal conductor 7D is connected to aland conductor 5B functioning as an input electrode or an outputelectrode via a via conductor 3 penetrating a second surface layer 22.The internal conductor 7E is connected to a land conductor 5A (see FIG.10 ) to be grounded via two via conductors (not illustrated) penetratingan intermediate layer 23I and the second surface layer 22.

As illustrated in FIG. 11 , the internal conductor 7D and the groundedinternal conductor 7E are arranged so as to face each other in thelamination direction. Therefore, the internal conductors 7D and 7Efunction as a capacitor 17D. The surface conductor 4F is connected tothe grounded internal conductor 7E via nine via conductors 3 penetratinga first surface layer 21 and eight intermediate layers 23A to 23H. Thesurface conductor 4F is connected to the internal conductor 7D via tenvia conductors 3 penetrating the first surface layer 21 and nineintermediate layers 23A to 23I. The surface conductor 4F and the viaconductor 3 connecting the surface conductor 4F and each of the internalconductors 7D and 7E constitute an inductor 9D. The inductor 9D and thecapacitor 17D form an LC parallel resonator.

Similarly, the internal conductor 7A and the internal conductor 7E arearranged so as to face each other in the lamination direction, therebyfunctioning as the capacitor 17A. The surface conductor 4C is connectedto each of the internal conductors 7A and 7E via the plurality of viaconductors 3. The surface conductor 4C and the via conductor 3connecting the surface conductor 4C and each of the internal conductors7A and 7E constitute an inductor 9A. The inductor 9A and the capacitor17A form an LC parallel resonator.

The via conductor 3 connected to each of the surface conductors 4C and4F is an example of a “connection conductor” in the present disclosure.

As illustrated in FIG. 10 , the surface conductor 4G is further providedon the surface 21 a of the first surface layer 21. Both end portions ofthe surface conductor 4G are connected to the surface conductors 4C and4F. The surface conductor 4G has a meander shape when viewed from thelamination direction. As a result, the surface conductor 4G functions asan inductor 9E. That is, the two LC parallel resonators areelectromagnetically coupled and electrically connected by the inductor9E.

According to the electronic component 1D according to the fourthembodiment, since the surface conductor 4 is thick in at least a part ofthe inductors 9A, 9D, and 9E, a larger conductor cross section can beobtained. This reduces the insertion loss of the inductors 9A, 9D, and9E. In addition, since the trimmable thickness of the surface conductor4 is large, the adjustment range of the electrical characteristics ofthe inductors 9A, 9D, and 9E is large.

Fifth Embodiment

Next, an electronic component according to a fifth embodiment of thepresent disclosure will be described with reference to FIGS. 12 and 13 .FIG. 12 is a plan view of the electronic component according to thefifth embodiment of the present disclosure. FIG. 13 is a cross-sectionalview of the electronic component taken along line A5-A5 in FIG. 12 .

An electronic component 1E according to the fifth embodiment isdifferent from the electronic component 1D according to the fourthembodiment in that a surface conductor 4 provided on a surface 21 a of afirst surface layer 21 has a spiral shape when viewed from thelamination direction.

As illustrated in FIG. 12 , the electronic component 1E includes onesurface conductor 4, an internal conductor 7D, and a grounded internalconductor 7E. Similarly to the electronic component 1D according to thefourth embodiment, the internal conductor 7D and the grounded internalconductor 7E face each other in the lamination direction to constitute acapacitor 17D.

The surface conductor 4 has a spiral shape when viewed from thelamination direction. That is, the surface conductor 4 is a coil whosewinding axis direction is the lamination direction (the depth directionof the paper surface in FIG. 12 ), and constitutes an inductor 9F. Asillustrated in FIG. 13 , the inner end portion of the spiral shape ofthe surface conductor 4 is connected to the internal conductor 7E viathe nine via conductors penetrating the first surface layer 21 and theeight intermediate layers 23A to 23H. The outer end portion of thespiral shape of the surface conductor 4 is connected to the internalconductor 7D via the plurality of via conductors 3 (see FIG. 12 ).

The via conductor 3 connected to the surface conductor 4 is an exampleof a “connection conductor” in the present disclosure.

As illustrated in FIG. 13 , the surface conductor 4 includes a firstportion 41 and a second portion 42 that is continuous with the firstportion 41 along the surface 21 a of the first surface layer 21 and isthinner in the lamination direction than the first portion 41. Thethickness T4 of the first portion 41 is larger than the thickness T2 ofthe intermediate layer 23A and larger than the thickness of the internalconductor 7. For example, the thickness T4 of the first portion 41 islarger than the thickness of the thickest internal conductor 7 of theelectronic component 1E. In the present embodiment, the thickness of thefirst portion 41 is larger than twice the thickness T2 of theintermediate layer 23A and larger than the thickness T3 of theintermediate layer 23D. In addition, the thickness of the first portion41 may be thicker than twice the thickness T3 of the intermediate layer23D.

In the present embodiment, as illustrated in FIG. 12 , the width of thefirst portion 41 when viewed from the lamination direction is smallerthan the width of the second portion 42 when viewed from the laminationdirection. The width of the first portion 41 may be thicker than thewidth of the second portion 42 or may be the same as the width of thesecond portion 42.

Sixth Embodiment

Next, an electronic component according to a sixth embodiment of thepresent disclosure will be described with reference to FIGS. 14 to 15 .FIG. 14 is a plan view of the electronic component according to thesixth embodiment of the present disclosure. FIG. 15 is a cross-sectionalview of the electronic component taken along line A6-A6 in FIG. 14 .

An electronic component 1F according to the sixth embodiment isdifferent from the electronic component 1E according to the fifthembodiment in that the electronic component 1F includes a coil-shapedinductor 9G whose winding axis direction is a direction intersecting thelamination direction.

As illustrated in FIG. 14 , the electronic component 1F includes threesurface conductors 4, two internal conductors 7, and two inductorconductors 18A and 18B. The three surface conductors 4 include surfaceconductors 4H to 4J. The two internal conductors 7 include internalconductors 7D and 7E. Similarly to the electronic component 1D accordingto the fourth embodiment, the internal conductor 7D and the groundedinternal conductor 7E face each other in the lamination direction toconstitute a capacitor 17D.

Each of the surface conductors 4 extends in the short-side direction(up-down direction in FIG. 14 ) of the outer shape of the electroniccomponent 1F when viewed from the lamination direction. In the presentembodiment, the three surface conductors 4 are arranged in anon-rotationally symmetric manner with respect to the virtual centerpoint of the electronic component 1F when viewed from the laminationdirection.

As illustrated in FIG. 15 , the inductor conductor 18B is formed in anintermediate layer 23G. That is, the inductor conductor 18B is formedbetween the intermediate layer 23F and the intermediate layer 23H. Thethickness of the inductor conductor 18B is the same as or substantiallythe same as the thickness of the intermediate layer 23G. Similarly, theinductor conductor 18A (not illustrated in FIG. 15 ) is also formed inthe intermediate layer 23G (that is, a portion between the intermediatelayer 23F and the intermediate layer 23H). The inductor conductors 18Aand 18B are formed, for example, by filling holes formed in portionscorresponding to the inductor conductors 18A and 18B of the insulatinglayer sheet 12 (described later) with a conductive paste 16 (describedlater) and firing the paste 16.

One end portion of the surface conductor 4J is connected to the internalconductor 7D via ten via conductors 3 penetrating a first surface layer21 and nine intermediate layers 23A to 23I. The other end portion of thesurface conductor 4J is connected to one end portion of the inductorconductor 18B via seven via conductors 3 penetrating the first surfacelayer 21 and the six intermediate layers 23A to 23F. As illustrated inFIG. 14 , the other end portion of the inductor conductor 18B isconnected to one end portion of an end portion of the surface conductor4I closer to one end portion of the surface conductor 4J via the viaconductor 3. The other end portion of the surface conductor 4J isconnected to one end portion of the inductor conductor 18A via the viaconductor 3. The other end portion of the inductor conductor 18A isconnected to one end portion of the end portion of the surface conductor4H closer to one end portion of the surface conductor 4I via the viaconductor 3. The other end portion of the surface conductor 4H isconnected to the internal conductor 7E via the via conductor 3.

The surface conductor 4, the inductor conductor 18A, 18B, and the viaconductor 3 connecting the surface conductor 4 and the inductorconductor 18A, 18B or each of the internal conductors 7D and 7Econstitute the inductor 9G. The inductor 9G is a coil whose winding axisdirection is a long-side direction of the outer shape of the electroniccomponent 1F when viewed from the lamination direction. The viaconductor 3 connected to each surface conductor 4 is an example of a“connection conductor” in the present disclosure.

As illustrated in FIG. 15 , each surface conductor 4 includes a firstportion 41 and a second portion 42 that is continuous with the firstportion 41 along a surface 21 a of the first surface layer 21 and isthinner in the lamination direction than the first portion 41. In theexample illustrated in FIG. 15 , a surface conductor 4J includes twofirst portions 41 and a second portion 42 arranged between the two firstportions 41.

The thickness T4 of the first portion 41 is larger than the thickness T2of the intermediate layer 23A and larger than the thickness of theinternal conductor 7. For example, the thickness T4 of the first portion41 is larger than the thickness of the thickest internal conductor 7 ofthe electronic component 1F. In the present embodiment, the thickness ofthe first portion 41 is larger than twice the thickness T2 of theintermediate layer 23A and larger than the thickness T3 of theintermediate layer 23D. In addition, the first portion 41 may be thickerthan twice the thickness T3 of the intermediate layer 23D. The thicknessT4 of the first portion 41 is, for example, 50 μm. The thickness T5 ofthe second portion 42 is, for example, 25 μm.

A boundary portion 43 between the first portion 41 and the secondportion 42 is arranged in a non-rotationally symmetric manner withrespect to the virtual center point of the electronic component 1F whenviewed from the lamination direction. In the boundary portion 43, ashadow S1 is generated due to a difference in thickness between thefirst portion 41 and the second portion 42. FIG. 14 illustrates theshadows S1 generated when the electronic component 1F is illuminatedfrom slightly above both end portions of the surface conductor 4.

According to the electronic component 1F according to the sixthembodiment, there is a difference in thickness at the boundary portion43 between the first portion 41 and the second portion 42, and theshadow S1 is generated at the boundary portion 43. The shadow S1 can beused as a directional mark indicating the direction of the electroniccomponent 1F. This eliminates the need to separately provide adirectional mark, so that the manufacturing efficiency of the electroniccomponent 1F can be improved. In addition, since the area occupied bythe directional mark is unnecessary on the surface 21 a of theinsulating layer 2, it is possible to reduce the size of the electroniccomponent 1F and to further arrange wiring, components, and the like.

<<Method for Manufacturing Electronic Component>>

Next, an example of a method for manufacturing an electronic componentaccording to the present disclosure will be described with reference toFIGS. 16 to 24 . FIGS. 16 to 24 are cross-sectional views illustratingan example of a method for manufacturing an electronic componentaccording to the present disclosure. In FIGS. 21 and 24 , a boundaryline between a forming sheet 11 and an insulating layer sheet 12 (bothwill be described later) and a part of the conductive paste 16(described later) are omitted for convenience of description.

As illustrated in FIG. 21 , the electronic component 1 is manufacturedby dividing a laminated body 10 into a plurality of laminated pieces101. The laminated body 10 is formed by integrating the plurality oflaminated pieces 101 in an arranged state. Each laminated piece 101corresponds to one electronic component 1. In FIGS. 16 to 20 , forconvenience of description, only a portion corresponding to onelaminated piece 101 of the laminated body 10 is illustrated.

(Sheet Forming Step)

In the manufacture of the electronic component 1, first, as illustratedin FIG. 16 , the forming sheet 11 for forming the surface conductor 4and the insulating layer sheet 12 constituting the insulating layer 2are formed. By mixing raw materials including a main agent, aplasticizer, a binder, and the like corresponding to each of the sheets11 and 12, a slurry constituting each of the sheets 11 and 12 isprepared.

For the forming sheet 11, for example, a resin that burns out duringfiring (described later), a non-sinterable ceramic powder, or the likeis used as a main agent. As a result, the forming sheet 11 can be burnedout during firing or can be removed by cleaning after firing.

For the insulating layer sheet 12, for example, a sinterable ceramicpowder or the like is used as a main agent. As the plasticizer, forexample, phthalic acid ester or di-n-butyl phthalate is used. As thebinder, for example, an acrylic resin, polyvinyl butyral, or the like isused.

The slurry constituting each of the sheets 11 and 12 is formed into asheet shape on a carrier film 13 using, for example, a lip coater, adoctor blade, or the like. As a result, the sheets 11 and 12 asillustrated in FIG. 16 are obtained. As the carrier film 13, forexample, a polyethylene terephthalate (PET) film or the like is used.The thickness of the forming sheet 11 is, for example, 1 to 150 μmbefore firing. In addition, the thickness of the insulating layer sheet12 is set to, for example, a thickness such that the thickness afterfiring is 1 to 150 μm.

In the present manufacturing example, two forming sheets 11A and 11B(see FIGS. 17 and 18 ) for forming the surface conductor 4 andinsulating layer sheets 12A to 12E (see FIGS. 17 to 19 ) for preparingfive insulating layers 2A to 2E (see FIGS. 22 and 23 ) are prepared.

(Hole Portion Forming Step)

Next, as illustrated in FIG. 17 , a surface conductor hole portion 111penetrating the forming sheet 11 and the carrier film 13 is formed. Inaddition, in a case where an electronic component including the viaconductors 3 is manufactured, via conductor hole portions 121penetrating the insulating layer sheet 12 and the carrier film 13 areformed. For forming each hole portion 111,121, for example, a mechanicalpunch, a UV laser, a CO₂ laser, or the like is used.

(Filling Step)

Next, as illustrated in FIG. 18 , each hole portion 111,121 is filledwith the conductive paste 16. The conductive paste 16 is prepared, forexample, by mixing raw materials containing a conductive powder, aplasticizer, and a binder. In addition, for example, a eutectic materialsuch as a ceramic powder mixed in each of the sheets 11 and 12 may beadded to the conductive paste 16 in order to adjust the shrinkage rateduring firing.

(Conductor Forming Step)

Next, as illustrated in FIG. 19 , conductors thinner than the surfaceconductor 4 such as the land conductor 5 and the internal conductor 7are formed. The conductive paste 16 is formed on the surface of theinsulating layer sheet 12 by, for example, screen printing, inkjetprinting, gravure printing, or the like. The composition of theconductive paste 16 may be changed according to the applied conductor.

(Lamination Step)

Next, as illustrated in FIG. 20 , the sheets 11 and 12 excluding thecarrier film 13 are laminated and pressure-bonded in a mold. By thesteps so far, the laminated body 10 is obtained.

(Dividing Step)

Next, as illustrated in FIG. 21 , the laminated body 10 is cut intolaminated pieces 101 corresponding to one electronic component 1. Forcutting the laminated body 10, for example, a dicing saw, a guillotinecutter, a laser, or the like is used. After the laminated body 10 iscut, the corners and edges of the laminated piece 101 may be polishedby, for example, barrel processing or the like.

(Firing Step)

Then, by firing the laminated piece 101, the insulating layers 2A to 2E,the via conductors 3, the surface conductor 4, the land conductor 5, andthe internal conductors 7 are obtained. At this time, in a case wherethe forming sheet 11 is configured to burn out, the forming sheet 11 isremoved as illustrated in FIG. 22 . In addition, in a case where theforming sheet 11 is configured not to burn out, the forming sheet 11 isremoved by cleaning the laminated piece 101 after firing.

(Trimming Step)

Then, as illustrated in FIG. 23 , the surface conductor 4 is trimmed asnecessary. As a result, the electrical characteristics of an element orthe like are adjusted. At this time, since the first portion 41 of thesurface conductor 4 is thicker than the second portion 42, only thefirst portion 41 can be trimmed by a planar processing method. Examplesof the planar processing method include etching and surface grinding.

When trimming is performed by surface grinding, for example, asillustrated in FIG. 24 , the plurality of laminated pieces 101 arearranged such that the surface corresponding to the surface 22 a of thesecond surface layer 22 is in contact with an adhesive sheet 202arranged on a stage 201. At this time, the surface conductors 4 providedon the laminated pieces 101 face the opposite side (the upper side inFIG. 24 ) of the stage 201. By bringing a grindstone 203 into contactwith the surface conductors 4 provided on the plurality of laminatedpieces 101, it is possible to simultaneously perform planar processingon the plurality of laminated pieces 101.

By the trimming, the thickness of the surface conductor 4 is reduced.That is, the conductor cross-sectional area of the surface conductor 4decreases. As a result, the electrical characteristics of an element orthe like including the surface conductor 4 can be adjusted. For example,in the second embodiment in which the surface conductor 4 constitutes apart of the inductor 9, when the surface conductor 4 is trimmed, theinductance value of the inductor 9 increases. As a result, when theinductor 9 constitutes a part of the resonator, the resonance frequencyof the resonance circuit decreases.

Through the above steps, the electronic component 1 in which the surfaceconductor 4 is exposed is manufactured. Further, when the plating film6, the resin layer 8, and the like are formed, the electronic component1A illustrated in FIGS. 1 to 3 , the electronic component 1B illustratedin FIGS. 4 to 6 , and the like are obtained.

<<Resin Layer Forming Method>>

Next, an example of a resin layer forming method for the electroniccomponent according to the present disclosure will be described withreference to FIGS. 25 to 27 . FIGS. 25 to 27 are views illustrating anexample of a resin layer forming method for the electronic componentaccording to the present disclosure.

In the present forming method, the electronic component 1B illustratedin FIGS. 4 to 6 is obtained by further forming the resin layer 8 on theelectronic component 1 manufactured by the above-described method.

(Immersion Step)

First, as illustrated in FIG. 25 , the electronic component 1manufactured as described above is immersed in a liquid resin 31. As aresult, the resin 31 adheres to the outer surface of the electroniccomponent 1. As the resin 31, a resin that can be cured only in adesired region is selected. Examples of the resin 31 include athermosetting resin and an ultraviolet curable resin.

After the immersion, as illustrated in FIG. 26 , the electroniccomponent 1 is arranged on an adhesive surface of an adhesive sheet 32with the vertical direction aligned.

(Curing Step)

Next, the resin 31 attached to the region of the electronic component 1where the resin layer 8 is to be formed is subjected to a curingtreatment to form the resin layer 8. For example, when a thermosettingresin is used, as illustrated in FIG. 26 , a hot plate 33 is pressedagainst the upper surface of the electronic component 1, whereby onlythe resin 31 attached to the upper surface can be cured.

When an ultraviolet curable resin is used, the resin 31 can be cured byirradiating a desired region including at least a part of the surfaceconductor 4 with ultraviolet rays. In addition, by applying a mask thatdoes not transmit ultraviolet rays to a region where the resin layer 8is not formed, formation of the resin layer 8 outside a desired regioncan be prevented.

(Removal Step)

Next, the uncured resin 31 is removed from the electronic component 1.For example, as illustrated in FIG. 27 , the uncured resin 31 is removedby cleaning the electronic component 1 in a cleaning liquid 34. Throughthe above steps, the electronic component 1B including the resin layer 8is manufactured.

According to this forming method, the resin layer 8 can be formed byattaching the resin 31 to the entire electronic component 1 and curingthe resin 31 only at a desired portion on the electronic component 1.Therefore, unlike the method for forming the resin layer 8 by applyingthe resin 31 only to a desired portion, it is not necessary to align theelectronic components 1 in order to attach the resin 31. Therefore, themanufacturing efficiency of the electronic component 1B can be improved.

Note that the present disclosure is not limited to the embodiments andthe example of the manufacturing method, and can be implemented invarious other modes. For example, in the above description, theelectronic components 1A to 1F include the five or eleven insulatinglayers 2, but the present disclosure is not limited thereto. Theelectronic components 1A to 1F only need to include at least oneinsulating layer 2, and the number of laminated layers is not limited.

In the above description, the via conductor 3 is an example of theconnection conductor, but the connection conductor is not limited to thevia conductor 3. For example, the connection conductor may be a wiringpattern (not illustrated) formed on the front surface 21 a of the firstsurface layer 21, the land conductor 5 (see FIG. 1 ), or the like. Inaddition, the “plurality of connection conductors” in the presentdisclosure may be one of the via conductors 3, the wiring patterns, theland conductors 5, and the like, or may be a combination thereof.

In the above description, the first portions 41 of the surface conductor4A and the surface conductor 4B are trimmed in the thickness direction,but the present disclosure is not limited thereto. The surface conductor4 may be trimmed not only in the thickness direction but also in thewidth direction. In the surface conductor 4B, only a part of the firstportion 41 of the surface conductor 4B may be trimmed. In addition, thesecond portion 42 may be trimmed. As the trimming method, not only aplanar processing method but also a method using a laser, for example,can be adopted. The trimming step is a step performed as necessary, andis not an essential step in the manufacture of the electronic components1, 1A, and 1B.

In the above description, the surface conductor 4 is arranged on thesurface 21 a of the first surface layer 21, but may be arranged onanother surface. For example, the surface conductor 4 may be arranged onthe surface 22 a of the second surface layer 22, or may be arranged onboth the surface 21 a of the first surface layer 21 and the surface 22 aof the second surface layer 22.

In the second embodiment, the three surface conductors 4 are arranged inparallel to each other, but the present disclosure is not limitedthereto. The number of surface conductors 4 may be arbitrary. Inaddition, even when the surface conductors 4 constitute a part of theinductor, the surface conductors 4 are not necessarily arranged inparallel.

In the second embodiment, the “inductor conductor” in the presentdisclosure is the internal conductor 7, but the present disclosure isnot limited thereto. The “inductor conductor” in the present disclosureonly needs to be electrically connected to the surface conductor 4 viathe via conductor 3, and may be, for example, a conductor formed on theinsulating layer 2, a conductor formed on the surface 22 a of the secondsurface layer 22, wire bonding, or the like.

In the second embodiment, the winding axis direction of the inductor 9is the direction in which the insulating layer 2 extends and thedirection perpendicular to the direction in which the surface conductor4 extends, but the present disclosure is not limited thereto. Thewinding axis direction of the inductor 9 is not particularly limited,and may be, for example, the lamination direction of the insulatinglayer 2.

In the second embodiment, the surface conductor 4 is covered with theresin layer 8, but may be covered with a glass layer instead of theresin layer 8. Even when the surface conductor 4 is covered with theglass layer, the same effect as the above-described effect by the resinlayer 8 covering the surface conductor 4 is achieved.

In the second embodiment, the resin layer 8 is formed on the entiresurface 21 a of the first surface layer 21, but the present disclosureis not limited thereto. For example, the resin layer 8 may be formedsuch that the thickness from the first surface layer 21 is thinner thanthat of the surface conductor 4 and the resin layer 8 surrounds thesurface conductor 4 in plan view.

In the above description, the resin layer 8 is formed by immersing theelectronic component 1 in the liquid resin 31, but the method forforming the resin layer 8 is not limited thereto. For example, the resinlayer 8 may be formed by applying a resin only to a desired region ofthe electronic component and curing the resin. Examples of the applyingmethod in such a case include screen printing, inkjet printing, anddispensing.

Note that, by appropriately combining any embodiments from the variousembodiments described above, the effects of the respective embodimentscan be achieved.

Although the present disclosure has been fully described in connectionwith preferred embodiments with reference to the accompanying drawings,various modifications and corrections will be apparent to those skilledin the art. Such modifications and corrections are to be understood asbeing included within the scope of the present disclosure as set forthin the appended claims as long as they do not depart therefrom.

Since the electronic component according to the present disclosure has alarge trimmable thickness of a conductor and a large adjustment range ofelectrical characteristics of an element or the like, it is useful foran electronic component or the like that requires trimming of aconductor.

-   -   1, 1A-1F electronic component    -   2, 2A-2E insulating layer    -   21 first surface layer    -   21 a surface    -   22 second surface layer    -   22 a surface    -   23, 23A-231 intermediate layer    -   3 via conductor    -   4, 4A-4J surface conductor    -   41 first portion    -   42 second portion    -   43 boundary portion    -   5, 5A, 5B land conductor    -   6 plating film    -   7, 7A-7E internal conductor    -   8 resin layer    -   8 a outer surface    -   9, 9A-9G inductor    -   10 laminated body    -   101 laminated piece    -   11, 11A, 11B forming sheet    -   111 surface conductor hole portion    -   12, 12A-12E insulating layer sheet    -   121 via conductor hole portion    -   13 carrier film    -   16 conductive paste    -   17A-17D capacitor    -   18A, 18B inductor conductor    -   31 resin    -   32 adhesive sheet    -   33 hot plate    -   34 cleaning liquid    -   201 stage    -   202 adhesive sheet    -   203 grindstone

1. An electronic component comprising: a plurality of laminatedinsulating layers; one or more surface conductors formed on a surface ofthe insulating layers; and at least one internal conductor formed at aboundary portion between adjacent ones of the insulating layers, whereina thickness of each of the surface conductors is more than a thicknessof a thinnest layer of the insulating layers and more than a thicknessof the internal conductor.
 2. An electronic component according to claim1, wherein the thickness of each of the surface conductors is more thantwice the thickness of the thinnest layer of the insulating layers. 3.An electronic component according to claim 1, wherein the thickness ofeach of the surface conductors is more than the thickness of thethickest layer of the insulating layers.
 4. An electronic componentaccording to claim 1, wherein a plating film is formed on at least apart of the surface of the surface conductors.
 5. The electroniccomponent according to claim 1, further comprising: a plurality ofconnection conductors formed inside the insulating layers or on thesurface of the insulating layers and connected to one of the surfaceconductors, wherein the at least one internal conductor comprises aplurality of internal conductors, and wherein the plurality ofconnection conductors are connected to the internal conductors differentfrom each other.
 6. An electronic component according to claim 5,wherein at least one of the plurality of connection conductors is a viaconductor penetrating one of the plurality of insulating layers in alamination direction of the insulating layers.
 7. An electroniccomponent according to claim 5, further comprising an inductor conductorelectrically connected to the surface conductors via the connectionconductors, wherein the surface conductors constitute at least a part ofan inductor together with the connection conductor and the inductorconductor.
 8. An electronic component according to claim 1, wherein thesurface conductors comprise: a first portion being thicker than thethickness of the thinnest layer of the insulating layers and beingthicker than the thickness of the internal conductor; and a secondportion being continuous with the first portion along the surface of theinsulating layers and being thinner than the first portion.
 9. Anelectronic component according to claim 8, having a rotationallysymmetric outer shape in plan view, wherein a boundary portion betweenthe first portion and the second portion in the surface conductors isarranged in a non-rotationally symmetric manner with respect to a centerpoint of the rotational symmetry of the electronic component.
 10. Anelectronic component according to claim 1, having a rotationallysymmetric outer shape in plan view, wherein the surface conductors arearranged in a non-rotationally symmetric manner with respect to a centerpoint of the rotational symmetry of the electronic component in planview.
 11. An electronic component according to claim 1, furthercomprising a resin layer or a glass layer covering at least a part ofthe surface conductors.
 12. An electronic component according to claim11, wherein at least a part of the resin layer or at least a part of theglass layer is thicker than a thickness of a thinnest layer of theinsulating layers and thicker than a thickness of the internalconductor.
 13. An electronic component according to claim 1, furthercomprising a via conductor penetrating one of the plurality ofinsulating layers in the lamination direction of the insulating layers,wherein the thickness of each of the surface conductors is more than alength of the via conductor in the lamination direction.
 14. Anelectronic component according to claim 13, wherein the surfaceconductors comprise: a first portion being thicker than the length ofthe via conductor in the lamination direction; and a second portionbeing continuous with the first portion along a surface of theinsulating layers and being thinner than the first portion.
 15. Anelectronic component according to claim 1, wherein the surfaceconductors constitute at least a part of an inductor.
 16. A resin layerforming method for an electronic component comprising: an immersion stepof immersing an electronic component according to claim 1 in a resin toattach the resin to an outer surface of the electronic componentincluding a surface of the insulating layers; a curing step of curingthe resin attached to at least a part of the surface conductors to forma resin layer; and a removal step of removing uncured portions of theresin from the electronic component.
 17. An electronic componentaccording to claim 2, wherein the thickness of each of the surfaceconductors is more than the thickness of the thickest layer of theinsulating layers.
 18. An electronic component according to claim 2,wherein a plating film is formed on at least a part of the surface ofthe surface conductors.
 19. An electronic component according to claim3, wherein a plating film is formed on at least a part of the surface ofthe surface conductors.
 20. The electronic component according to claim2, further comprising: a plurality of connection conductors formedinside the insulating layers or on the surface of the insulating layersand connected to one of the surface conductors, wherein the at least oneinternal conductor comprises a plurality of internal conductors, andwherein the plurality of connection conductors are connected to theinternal conductors different from each other.